Editorial
Tsunami Induced Hyperglycemia and DiabetesMortality - Two studies from South India
Shashank R Joshi

Stress affects everyone and its subtypes namelywork-related stress, home stress and post-traumaticstress disorders (PTSD) are all health hazards. Stressand its comorbid diseases are responsible for a largeproportion of disability worldwide. The World HealthOrganization (WHO) Global Burden of Disease Surveyestimates that mental disease, including stress-relateddisorders, will be the second leading cause of disabilitiesby the year 2020. Although the term ‘stress’ is used in awide variety of contexts, it has consistently beendemonstrated that individuals with stress and relateddisorders experience impaired physical and mentalfunctioning, more work days lost, increased impairmentat work, and a high use of healthcare services. Thedisability caused by stress is just as great as the disabilitycaused by workplace accidents or other common medicalconditions such as hypertension, diabetes, and arthritis.1Natural calamities like earthquakes and tidal wavetsunamis have been known to cause PTSD and impactdiseases like diabetes though such reports are scant. TheGreat Hanshin-Awaji Earthquake worsened glycemiccontrol in Japanese diabetics in 1995.2 Similar resultswere seen in a rural community in Northern China whereinfluence of earthquake was noted on quality of life withtype 1 diabetes.3

A tidal wave swept South-East Asia on 26th December2004 which was a natural disaster. Tamil Nadu coastwas badly ravaged and this led to hardship and mentalstress. Since last year the Diabetes Research Centre,Chennai established in a village twice a week TsunamiOPD for diabetic patients. In this issue of JAPI,Ramachandran et al in two populations, one affected bytsunami (n=1184) and other control (n=1176), each morethan thousand patients use Harvard traumaquestionnaire and score as well as glucose tolerance test.Stress score was significantly higher in tsunamipopulation. Although the total prevalence of diabeteswas similar (control – 10.0%; tsunami population –10.5%) prevalence of undetected diabetes (5.7% vs 3.8%;Z = 9.54, P <0.001) and impaired glucose tolerance (9.8%vs 8.3%; Z = 12.83, P <0.001) were higher in the tsunamiarea. Stress score was higher in women and in the youngin the tsunami area. Population affected by tsunami was under high stress and also showed a high prevalence ofundetected diabetes and impaired glucose tolerance.4
Stress induced hyperglycemia is a well-known featureof “General Adaptation Syndrome” (arousal, resistance,exhaustion), but it is known to reverse. If a sub-population of Tsunami (or earthquake) affected personsturns diabetic after PTSD, then further studies arewarranted to study affected/non affected groups withreference to anxiety-depression scale. Earthquakesurvivors, terrorism affected and such groups can besubjected to retrospective cohort studies. The neuro-endocrine response to stress now is well studied and isa complex interplay of neuro peptides, cortisol-cortisoneaxis, epinephrine and other catecholamines as well asseveral other hormones. Currently there are more than150 published papers of ‘stress’ and ‘hyperglycemia’which have yielded variable results. Stress still remainsan poorly studied component in Asian Indianpopulation and the current study needs a long termfollow up to know its long term effects. TraditionallyIndian systems like yoga has always aimed at stressmodulation and need to be revisited.
Asian Indians have higher prevalence rates ofdiabetes, premature coronary artery disease [CAD] andcardiovascular disease [CVD] mortality compared toother ethnic groups.5 Diabetes is one of the leadingcauses for morbidity and mortality worldwide. In recentyears India has witnessed a rapidly exploding epidemicof diabetes.6 At present there are over 32 million diabeticindividuals in India and these numbers are predicted toincrease to nearly 80 million by the year 2030.7Environmental and lifestyle changes resulting fromindustrialization and migration to urban environmentfrom rural settings may be responsible to a large extent,for this epidemic of Type 2 diabetes in Indians. Inaddition, there is also strong evidence that Indians havea stronger genetic predisposition to diabetes.8 It is alsobeen shown that a typical Asian Indian phenotype withhigher percentage of body fat and increased waist tohip ratio or any given body mass index (BMI) whichpredisposes to diabetes and the metabolic syndrome.9
Earlier studies have shown that Indians have a highmortality rate due to diabetes. The number of deathsattributable to diabetes globally in 2000 was estimatedat 3.2 million, almost 6% of world mortality.10 A recentreport published by the Indian Council of Medical Research (ICMR), reported that in India, mortality dueto diabetes has increased from 0.95 lakh deaths/ year in1998 to 1.09 lakh deaths/ year in 2004.11
There are very few population-based studies onmortality rates in India and virtually none comparingdiabetic and non-diabetic subjects. However, informationon mortality rate and cause of death due to diabetes isavailable from some retrospective hospital-based andautopsy studies.12-14 There is therefore a need for suchstudies in India as there is a paradigm shift in the healthproblems in the country, from communicable disease tonon-communicable diseases (NCD’s), which includesdiabetes, cardiovascular diseases (CVD), hypertensionand obesity. However, diabetes is rarely perceived as amajor contributor to mortality, largely because routinemortality statistics are based on death certificates wherediabetes is often omitted as primary or secondary causeof death. It is a great challenge to study the mortalityrates among diabetic individuals as it leads to otherdisease conditions, which subsequently become thecause of death. According to the World HealthOrganization study13 there are about five times as manydeaths indirectly attributable to diabetes as directlyattributable in established market economies.
With this scenario of the diabetes burden, it isimportant to study the mortality rates due to diabetesusing population based Indian data to know the realdimensions of the problem and work towards preventivemeasures. The population based study done byDr.Mohan and his group following the cohort from thefamous Chennai Urban Population Study is animportant mortality study conducted in diabetic andnon-diabetic subjects from India.15 Of the 1262individuals who responded at baseline, 1140individuals [90.3%] could be followed annually for sixyears since 1997. The overall mortality rate was higherin diabetic, compared to non-diabetic, subjects [18.9vs.5.3 per 1000 person years]. Cardiovascular and renaldiseases were the commonest causes of death amongdiabetic subjects, whereas mortality due togastrointestinal, respiratory, lifestyle-related andunnatural causes were observed only among non-diabetic subjects. The hazards ratio for all causemortality for diabetes was 3.6, and even after adjustingfor age the ratio was 1.9 demonstrating that in urbanIndia, mortality rates are two-fold higher in people withdiabetes compared to non-diabetic subjects. It wassurprising to note that waist circumference andtriglyceride levels, which are markers of obesity andCAD, are found to be lower among the non-survivorscompared to the survivors.
Few studies have shown that compared to hostpopulations, migrant Indians have higher mortality ratesin diabetic subjects compared with non-diabeticsubjects.5 Hence data on mortality in diabetic individualsare extremely important and this study conducted by Mohan et al15 is an important study from India.Ramachandran et al study once again highlight theconnection of "stress and "diabetes" where evidence basehas been a little conflicting but gathering momentum.The current emerging evidence suggest both a moredirect role as well as an indirect role of "stress" mediatedvia cortisol axis in the visceral fat, the cortisol - cortisoneshuttle. Thus in this issue two landmark studies bothfrom Chennai from wellknown diabetes centers arepublished. One highlights the impact of Tsunami andTsunami related stress on hyperglycemia, undetecteddiabetes and impaired glucose tolerance and shows usthe contribution of stress in diabetes which is so ill-recognised. This should re-emphasize the point thatlifestyle modifications should integrate stressmanagement including Yoga as a part of comprehensivemetabolic care. The second study highlights the burdenof diabetes and its impact on mortality. The burden ofdiabetes is not just due to diabetes itself but the vascularburden and mortality it will contribute. To reducemortality due to diabetes early detection of diabetes andtight control of blood glucose, pressure, lipids and otherathero-thrombotic factors is needed.
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